Thermostat



Oct. 9, 1928. 1,687,230

W. J. SMITH THERMOSTAT Filed Aug. 24, 1926 Waugh/1 J 517232170 Patented I 9, 192,8.

WELLINGTON J. SMITH, OF CLEVELAND, OHIO.

THERMOSTAT.

Application filed August 24, 1926. Serial No. 131,241.

This invention relates to a thermostat controller, and particularly to a construction embodying a metallic bar ofthermostatic character disposed to cooperate with a make-andbreak circuit mechanism for the purpose of maintaining a uniform predetermined temperature in a compartment.

The invention especially relates to the 011'- cuit contact members comprising a fixed contact and a lever or movable contact having one end disposed in the path of a thermostatic bar so as to be thereby actuated together with means by which the contact members adjusted relative to the bar.

The invention has for an object to provide a novel and improved construction in which a contact closing unit is' mounted for adjustment relative .to the free end of a ther mostatic metal bar so as to thereby determine the temperature to be maintained in the compartment in which the heating means is controlled by the thermostat. T

A further object of the invention is to providean improved construction of the circuit contact members in which the movable member comprises a pivoted lever normally tensioned towards a fixed contact and adapted to be moved against said tension in the ex I pensive action of a thermostatic metal bar.

Another object of the invention is to provide the contact members as a unit construction mounted upon an adjusting device by which they may be bodily shifted so that the circuit to an electric heater will be opened at the proper temperature dependent upon the adjustment previously made and controlled by the expansive capacity of the thermostatic bar under the temperature ofv the compartment. 7

Other and further objects and advantages of the invention will be hereinafter set forth and the novel features thereof defined by the appended claims.

In the accompanying drawing Figure 1 is a side elevation of the device applied, with parts in section;

Figure 2 is a plan thereof;

Figure 3'is an end view; and

Figure 1 is a detail perspectiveof the contact members. 1

Like reference numerals designate corresponding parts throughout the several figures of the drawing.

The invention is designed. for various apmay be plications and for the control of different heating devices, and in the form here shown comprises an insulating base'lO adapted to be mounted within a compartment 11 to be heated which may be a brooder, insulator, or other enclosure adapted to be heated by an electric heater, as indicated at 12, having a current source at 13. The base 10 has mounted at one end thereof a bar or arm 14 of suitable thermostatic character such as the ordinary laminated metals, this bar being offset from the base and secured thereto at 15. The free end .16 of the bar is adapted for expansion and contraction toward and from the base as indicated by dotted lines in Figure 1 and overlaps-a circuit contact lever 17. This lever may be of various constructions,'a desirable form being herein shown aspivoted at 18in the depending ears 19. of a frame 20. This frame is formed with a depending arm 21 carrying a fixed circuit contact 22 from which a conductor 23 extends to the heater 12 or other device.

Cooperating with the contact 22 is the movable cont-act 24 carried by the end of the lever l7 and normally tensioned toward the fixed contact by a spring 25. This spring main tains the contacts in closed position establishing a heating circuit and such circuit is broken by the engagement of the free end 16 of the thermostaticbar with the end 26 of the lever 17, as indicated in Figure 1. For the purpose of spacing the ends 16 and 26 to control the temperature at which the circuit will be opened, an adjusting device of suitable character is mounted upon the base 10. This may comprise a screw 27 threaded through the base and connected by a swivel at 28 with the frame 20 carrying the contact members so that they are bodily adjusted. The screw is provided with a hand hold 29 extended through the casing of the compartment to be heated and the movement of the unit carrying the contact members is guided by one or more pins 30 extending through an aperture in the lug'31 from the frame 20. The contact member 24 upon the lever 17 is connected to the conductor 32 in any desired manner, for in which it will be seen that the contact memwill be a pparent'from the foregoing description'from bers are normally closed. until the tempera:

ture of the compartment is raised to a degree sufiicient to actuate the thermostatic bar which by its contact with the movable member opens or breaks the circuit and thus provides means for maintaining a predetermined uniform temperature] in the compartment. The mounting of the contact members in a separate unit provides for the convenient ap spaced relation to the thermostatic member.

While the specific construction oi the in vention has been shown and described, the invention is not confined thereto as changes and alterations may be made without departing from the spirit of the invention and the controllin members applied to a circuit for the contro of any desired device.-

I claim 2-.

' 1. In thermostatic controlled apparatus, a frame the combination with a support, 0 movably carried thereby, an arm outstandmg from the frame and having a return portion substantially parallel to the frame, a

lever pivoted to the frame and having a portion extending between the frame and return portion of the arm, a contact carried by the return portion of the arm, a contact carried by the ever' in position to engage the first mentioned contact, and thermally controlled means for swinging the lever for breaking such contact.

2. A unit for a thermostatic controller comprising an adjustable frame having a depending portion carrying a fixed contact, ears extendlng from said frame, and a lever piv-' oted mtermedlate its ends to said ears and carrying a contact member.

In testimony whereof I aflix my signature.

WELLINGTON J. SMITH. 

